Image display device, method, and program

ABSTRACT

It is an object of the present invention to search for image data with an intuitive operation to which active elements are added. 
     A digital photo frame  1  searches a non-volatile data base memory  15  or a network for image data based on parameters respectively related to a position and a direction in which the digital photo frame  1  is arranged, a distance or a depth from the digital photo frame  1 , and time. The digital photo frame  1  displays an image expressed by the image data thus searched.

The application is based on and claims the benefit of priority fromJapanese Patent Application No. 2009-219482 filed on Sep. 24, 2009, thecontent of which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an image display technique andparticularly to an image display device, a method and a program that candisplay an image by searching with an intuitive operation to whichactive elements are added, for example.

2. Related Art

An image display device such as a personal computer, a digital photoframe and the like determines image data of an image to be displayed bysearching an external memory card or built-in memory for the image data,or searching via a network such as wired or wireless LAN (Local AreaNetwork) or the like for the image data. According to a conventionalsearch method, when a viewer enters a keyword, the image display devicesearches for image data using the keyword and tag information written inmeta data of the image data (see Japanese Patent Unexamined PatentApplication Publication No. 2001-265780, for example).

SUMMARY OF THE INVENTION

However, with the conventional search method by way of a keyword,disclosed in Japanese Patent Unexamined Patent Application PublicationNo. 2001-265780 or the like, if the name of an image to be viewed isknown, the image can be found in a pinpoint manner; however, if theviewer has only a vague impression on the image to be viewed, acumbersome and time-consuming operation such as repeatedly inputtingsearch keywords is needed.

As mentioned above, with the conventional search method, it is onlypossible to view the image searched based on the keyword in a passivemanner. Therefore, it has not been possible for the viewer to search foran image with an intuitive operation including active elements and findan unpredictable and surprising image based on a vague impression otherthan entering a keyword. More specifically, the image that the viewerwould like to view based on a vague impression is likely to be stronglyrelated to an actual environment at which the viewer is present.However, with the conventional search method, every time a keyword isentered, image data relating to the keyword is repeatedly searchedwithout any relationship with the actual environment where the viewerviews an image, and it can be difficult to arrive at the image that isdesired to be viewed.

Therefore, realization of a method that can search for image data withan intuitive operation to which active elements are added has beendemanded; however, the current situation is that such a demand is notsufficiently accommodated.

The present invention was made in view of the above problems and it isan object of the present invention to provide an image display device, amethod, and a program that can search for and display image data with anintuitive operation to which active elements are added.

According to a first aspect of the present invention, an image displaydevice that searches for image data satisfying a predetermined searchcondition from among a plurality of image data associated withpositional information, and causes an image expressed by the image datato be displayed on a display portion, the image display deviceincluding: a search portion that searches for the image data associatedwith the positional information satisfying the search conditions using aposition and a direction in which the image display device is arrangedas the search conditions; and a control portion that causes an imageexpressed by the image data searched by the search portion to bedisplayed on the display portion is provided.

According to a second aspect of the present invention, an image displaydevice further including an arrangement positional information acquiringportion that acquires information on a position at which the imagedisplay device is arranged and an arrangement direction informationacquiring portion that acquires information on a direction where theimage display device is arranged, in which the search portion uses theposition indicated by the information acquired by the arrangementpositional information acquiring portion and the direction indicated bythe information acquired by the arrangement direction informationacquiring portion as the search conditions is provided.

According to a third aspect of the present invention, an image displaydevice further including a distance information acquiring portion thatacquires information on a distance or a depth using the image displaydevice as a basis, in which the search portion searches for the imagedata associated with the positional information satisfying the searchcondition to which the distance or depth indicated by the informationacquired by the distance information acquiring portion is added as thesearch condition is provided.

According to a fourth aspect of the present invention, an image displaydevice is provided in which the distance information acquiring portionacquires the information on distance or depth based on an operation froma user.

According to a fifth aspect of the present invention, an image displaydevice in which a time information acquiring portion that acquiresinformation on time is further included, in which the plurality of imagedata is further associated with time information, and the search portionsearches for the image data associated with the positional informationand time information satisfying the search conditions to which the timeindicated by the information acquired by the time information acquiringportion is further added as the search conditions is provided.

According to a sixth aspect of the present invention, an image displaydevice is provided in which the time information acquiring portionacquires the current time at least as a part of the time information.

According to a seventh aspect of the present invention, an image displaydevice is provided in which the time information acquiring portionacquires at least a part of the time information based on an operationfrom a user.

According to an eighth aspect of the present invention, an image displaydevice is provided further including a storage portion that stores theplurality of image data, in which the search portion searches for theimage data from the storage portion.

According to a ninth aspect of the present invention, an image displaydevice is provided further including a communication portion that iscapable of communication with an external device, in which the searchportion searches for the image data from the external device with whichthe communication portion communicates.

According to a tenth aspect of the present invention, an image displaymethod for searching for image data satisfying a predetermined searchcondition from among a plurality of image data associated withpositional information, and causing an image expressed by the image datato be displayed on an image display device, the image display methodincluding: a search step of searching for image data associated with thepositional information satisfying search conditions using a position anda direction in which the image display device is arranged as the searchconditions and a control step of causing an image expressed by the imagedata thus searched in the search step to be displayed on the imagedisplay device.

According to an eleventh aspect of the present invention, a program isprovided for causing a computer controlling an image display device,which searches for image data satisfying a predetermined searchcondition from among a plurality of image data associated withpositional information and displays an image expressed by the imagedata, to implement: a search function for searching for the image dataassociated with the positional information satisfying search conditionsusing a position and a direction in which the image display device isarranged as the search conditions and a control function for causing theimage display device to display the image expressed by the image datathus searched by the search function.

According to the present invention, it is possible to search for anddisplay image data with an intuitive operation to which active elementsare added.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view showing an exterior configuration of a digitalphoto frame constituting an embodiment of an image display deviceaccording to the present invention;

FIG. 2 is a diagram illustrating an outline of search processing ofimage data by the digital photo frame shown in FIG. 1;

FIG. 3 is a block diagram showing a configuration of hardware of thedigital photo frame shown in FIG. 1;

FIG. 4 is a flowchart showing an example of a flow of image displayprocessing by the digital photo frame shown in FIG. 1;

FIG. 5 is a diagram showing a specific example of an arrangementrelationship of the digital photo frame shown in FIG. 1; and

FIG. 6 is a set of diagrams respectively showing specific examples ofresults of the image display processing by the digital photo frame shownin FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

An embodiment of the present invention will be described below based onthe attached drawings.

An image display device according to the present invention can beconfigured by a digital photo frame, a personal computer, or the like. Acase in which the image display device is configured as a digital photoframe will be described hereinafter. FIG. 1 is a front view showing anexample of an exterior configuration of the digital photo frame.

On a front face of the digital photo frame 1, a display portion 11configured as a liquid crystal display or the like, for example, and atime knob 13 for adjusting a time parameter are provided. On a side faceof the digital photo frame 1, a distance direction knob 12 for adjustinga parameter of a distance or a depth is provided. It should be notedthat these parameters will be described later referring to the drawings,starting from FIG. 2.

FIG. 2 is a schematic diagram illustrating an outline of searchprocessing of image data by the digital photo frame 1.

As shown in FIG. 2, the digital photo frame 1 includes a CPU (CentralProcessing Unit) 14 and non-volatile database memory 15.

The CPU 14 executes various types of processing according to a programstored in ROM (Read Only Memory), not illustrated. Alternatively, theCPU 14 may execute various types of processing according to a programloaded from the non-volatile database memory 15 to RAM (Random AccessMemory), not illustrated. The RAM also stores data or the like requiredupon execution of the various types of processing by the CPU 14 asappropriate.

In the present embodiment, for example, the CPU 14 searches for imagedata and causes an image to be displayed on the display portion 11 basedon the image data thus searched. Hereinafter, the above series ofprocessing will be referred to as image display processing. In thepresent embodiment, the program for realizing such an image displayprocessing is stored in the ROM or the non-volatile database memory 15.Therefore, the CPU 14 executes the image display processing according tothis program.

The non-volatile database memory 15 stores various data in addition tothe above-mentioned program. For example, the non-volatile databasememory 15 stores image data to be searched by the CPU 14.

Moreover, in the present embodiment, the image data to be searched bythe CPU 14 is stored not only in the non-volatile database memory 15built into the digital photo frame 1, but also in a device on apredetermined network such as the Internet. That is, in the presentembodiment, the CPU 14 can search the non-volatile database memory 15and the network, respectively, for the image data of an image to bedisplayed.

As a search method of image data, the above-mentioned conventionalmethod, i.e. a method of searching for image data based on a keywordtyped by a viewer, can naturally be employed. Moreover, in the presentembodiment, a search method is employed in which a position and adirection in which the digital photo frame 1 is arranged and a distance(or a depth) based on the digital photo frame 1 and time are employed asparameters, respectively, and image data is searched based on these fourparameters. Hereinafter, the above search method will be referred to asa “parameter search method”.

FIG. 3 is a block diagram showing a configuration of hardware of thedigital photo frame 1 to which the parameter search method is applied.

Specifically, the digital photo frame 1 further includes, in addition tothe above-mentioned display portion 11 to the non-volatile databasememory 15, memory 16 including the above-mentioned ROM and RAM, a clockportion 17, a bus 18, a display driver 19, a buffer 20, a wirelesscommunication portion 21, an antenna 22, a buffer 23, a wiredcommunication portion 24, a GPS (Global Positioning System) 25, ageomagnetic sensor 26, an operation portion 27, and a drive 28.

The clock portion 17 keeps the current time. In the present embodiment,the current time kept by the clock portion 17 is used as a referencevalue for calculating a time parameter. As will be described later, itshould be noted that it is naturally possible to use the current time asa time parameter in an unaltered state.

The CPU 14, the non-volatile database memory 15, the memory 16, and theclock portion 17 are mutually connected through the bus 18. The displaydriver 19, the buffer 20, the buffer 23, the GPS 25, the geomagneticsensor 26, the operation portion 27, and the drive 28 are also connectedto this bus 18.

The display driver 19 acquires predetermined image data from thenon-volatile database memory 15 or other devices on the network (notillustrated), and displays an image expressed by the image data on thedisplay portion 11 as a display image.

The buffer 20 temporarily stores various data wirelessly communicated bythe wireless communication portion 21. The wireless communicationportion 21 controls wireless communication performed between otherdevices through the network including the Internet. This wirelesscommunication is performed through the antenna 22. The buffer 23temporarily stores various data that is communicated via wire by thewired communication portion 24. The wired communication portion 24controls wired communication performed between the other devices throughthe network including the Internet. As mentioned above, the digitalphoto frame 1 is capable of both wireless communication and wiredcommunication with the other devices through the network.

The GPS 25 measures a current position of the digital photo frame 1 bycalculating a distance from a plurality of GPS satellites. In thepresent embodiment, the CPU 14 acquires a measurement result of the GPS25 as a parameter of a position where the digital photo frame 1 isarranged. That is, a pair of the CPU 14 and the GPS 25 is an example ofan arrangement positional information acquiring portion.

The geomagnetic sensor 26 detects geomagnetism and measures a directionin which the digital photo frame 1 is arranged based on a detectionresult. In the present embodiment, the CPU 14 acquires a measurementresult of the geomagnetic sensor 26 as a parameter of a direction inwhich the digital photo frame 1 is arranged. That is, a pair of the CPU14 and the geomagnetic sensor 26 is an example of an arrangementdirection information acquiring portion.

The operation portion 27 receives an operation to the digital photoframe 1 and notifies the operation contents to the CPU 14. The operationportion 27 includes a distance direction knob 12 and a time knob 13,which are shown in FIG. 1.

Setting of the distance direction knob 12 is adjusted according to anoperation amount. In the present embodiment, the CPU 14 acquires a setvalue of the distance direction knob 12 as a parameter of a distance ora depth, with the digital photo frame 1 as a basis. That is, a pair ofthe distance direction knob 12 and the CPU 14 is an example of thedistance information acquiring portion.

Setting of the time knob 13 is adjusted according to an operationamount. In the present embodiment, the CPU 14 acquires, as a parameterof time, a value equal to a set value of the time knob 13 subtracted oradded to a reference value, which is the current time kept by the clockportion 17. That is, a group of the time knob 13, the CPU 14, and theclock portion 17 is an example of the time information acquiringportion.

Removable media 29 composed of a magnetic disk, an optical disk, amagnetic optical disk, a semiconductor memory, or the like is mounted tothe drive 28 as appropriate. Then, a program read out therefrom isinstalled in the non-volatile database memory 15 as necessary.

FIG. 4 is a flowchart showing an example of a flow of the image displayprocessing by the digital photo frame 1.

In Step S1, the CPU 14 controls the GPS 25 and the geomagnetic sensor26, and acquires a parameter of a position and a direction in which thedigital photo frame 1 is arranged.

In Step S2, the CPU 14 acquires a parameter of a distance or a depthbased on the setting of the distance direction knob 12.

In Step S3, the CPU 14 acquires a parameter of time based on the currenttime kept by the clock portion 17 and the setting of the time knob 13.

In Step S4, the CPU 14 determines whether a search destination of imagedata is within the digital photo frame 1 or not.

In a case of the search destination of the image data being within thedigital photo frame 1, it is determined to be YES in Step S4, and theprocessing proceeds to Step S5. In Step S5, based on the four parametersacquired in the processing from Step S1 to Step S3, the CPU 14 searchesthe non-volatile database memory 15 for the image data.

Specifically, in the present embodiment, the image data to be searchedis associated with the positional information and the time information.Herein, the information associated with the image data includesinformation such as so-called meta data, which is not contained in theimage data at the time of generation, but is later associated with theimage data. Moreover, the information associated with the image dataincludes information, which is potentially contained in the image data,and is later extracted from the image data by appropriate imageprocessing or image analysis at arbitrary timing including the timeduring execution of the image display processing, and then associatedwith the image data. The CPU 14 searches the non-volatile databasememory 15 for the image data associated with the positional informationand time information satisfying the search conditions, which are fourparameters acquired in the processing from Step S1 to Step S3. It shouldbe noted that the method of searching for the image data in Step S5 isnot particularly limited to the method of the present embodiment thusdescribed, and an arbitrary method can be applied as long as the fourparameters acquired in the processing from Step S1 to Step S3 areutilized.

In a case in which the search destination of the image data is outsidethe digital photo frame 1, it is determined to be NO in Step S4, and theprocessing proceeds to Step S6. In Step S6, the CPU 14 searches throughthe network for the image data based on the four parameters acquiredfrom the processing from Step S1 to Step S3. That is, the CPU 14controls the wireless communication portion 21 or the wiredcommunication portion 24 and transmits and receives various types ofinformation including the four parameters with the other devices on thenetwork so as to search the other devices for the image data andreceives the image data thus searched through the network.

It should be noted that, in the present embodiment, the method ofsearching for the image data in Step S6 is a method similar to theabove-mentioned method of searching for the image data in Step S5.

However, the method of searching for the image data in Step S6 is notlimited to the method of the present embodiment, and an arbitrary methodcan be applied as long as the four parameters acquired in the processingfrom Step S1 to Step S3 are utilized. In other words, the method ofsearching for the image data in Step S6 is not necessarily the same asthe method of searching for the image data in Step S5.

If the image data is found in the processing in Step S5 or Step S6, theprocessing proceeds to Step S7. In Step S7, the CPU 14 controls thedisplay driver 19, and causes the display image to be displayed on thedisplay portion 11 on the basis of the image data thus found.

As a result, the image display processing is terminated.

Hereinafter, the image display processing will be explained in detailwhile referring to FIGS. 5 and 6.

FIG. 5 is a diagram showing an example of an arrangement relationship ofthe digital photo frame 1.

In the example of FIG. 5, the digital photo frame 1 is arranged so thatits back face (the face opposite to the display face of the displayportion 11) is facing toward a direction D at a position P in the realworld. Then, in the real world, a tower 51 is present at a positionseparated only by a distance d1 from the position P in the direction D,and a mountain 52 is present at a position separated only by a distanced2.

If the image display processing in FIG. 4 is started while thepositional relationship in FIG. 5 is maintained, information indicativeof the position P as a positional parameter and information indicativeof the direction D as a directional parameter are acquired in theprocessing in Step S1.

It is herein assumed that the setting of the distance direction knob 12is a setting corresponding to the distance d1, a time zone of thecurrent time is noon, and the setting of the time knob 13 is a 0 setting(default setting), for example. In this case, in the processing in StepS2, information indicative of the distance d1 is acquired as a parameterof distance or depth. In the processing in Step S3, informationindicative of the time zone (the time zone of the current time) of noonis acquired as a time parameter. As a result, by means of the processingfrom Step S4 to Step S7, the non-volatile database memory 15 or theother devices on the network are searched for the image data on thetower 51 in the time zone (the time zone of the current time) of noon,and the image shown in FIG. 6A is displayed on the display portion 11based on this image data.

More specifically, it is assumed that the positional informationindicative of the existing position of the tower 51 and the timeinformation indicative of the time zone of noon are associated with theimage shown in FIG. 6A, for example. In this case, the position, whichis from the position P indicated by the positional parameter separatedby the distance d1 indicated by the distance or depth parameter towardthe direction D indicated by the directional parameter, matches theposition (existing position of the tower 51) indicated by the positionalinformation associated with the image shown in FIG. 6A. In addition, thetime zone of noon indicated by the time parameter (the time zone of thecurrent time) matches the noon time zone indicated by the timeinformation associated with the image shown in FIG. 6A. Therefore, theimage data of the image shown in FIG. 6A is found.

Subsequently, it is assumed that the distance direction knob 12 isoperated and the setting corresponding to the distance d1 is changed tothe setting corresponding to the distance d2. However, it is alsoassumed that the time knob 13 is not operated, and is kept at the 0setting (the default setting). In this case, in the processing in StepS2, information indicative of the distance d2 is acquired as a distanceor depth parameter. In the processing in Step S3, information indicativeof the time zone (the time zone of the current time) of noon is acquiredas a time parameter. As a result, through the processing from Step S4 toStep S7, the non-volatile database memory 15 or from the other deviceson the network are searched for the image data on the mountain 52 in thetime zone (the time zone of the current time) of noon, and the imageshown in FIG. 6B is displayed on the display portion 11 on the basis ofthe image data.

More specifically, it is assumed that the positional informationindicative of the existing position of the mountain 52 and the timeinformation indicative of the time zone of noon are associated with theimage shown in FIG. 6B, for example. In this case, the position, whichis from the position P indicated by the positional parameter separatedonly by the distance d2 indicated by the distance or depth parametertoward the direction D indicated by the directional parameter, matchesthe position (existing position of the mountain 52) indicated by thepositional information associated with the image shown in FIG. 6B. Inaddition, the time zone of noon indicated by the time parameter (thetime zone of the current time) matches the time zone of noon indicatedby the time information associated with the image shown in FIG. 6B.Therefore, the image data of the image shown in FIG. 6B is found.

Moreover, it is assumed that the time knob 13 is operated and the 0setting is changed to a setting corresponding to 12 hours later.However, it is also assumed that the distance direction knob 12 is notoperated, and is kept at the setting corresponding to the distance d2.In this case, in the processing in Step S2, information indicative ofthe distance d2 is acquired as a distance or depth parameter. In theprocessing in Step S3, information indicative of the time zone of 12hours after the current time, i.e. information indicative of a time zoneof night is acquired as a time parameter. As a result, through theprocessing from Step S4 to Step S7, the non-volatile database memory 15or the network is searched for the image data on the mountain 52 in thetime zone (the time zone of 12 hours after the current time) of night,and the image shown in FIG. 6C is displayed on the display portion 11 onthe basis of the image data.

More specifically, it is assumed that the positional informationindicative of the existing position of the mountain 52 and the timeinformation indicative of the time zone of night are associated with theimage shown in FIG. 6C, for example. In this case, the position, whichis from the position P indicated by the positional parameter separatedby the distance d2 indicated by the distance or depth parameter towardthe direction D indicated by the directional parameter, matches theposition (existing position of the mountain 52) indicated by thepositional information associated with the image shown in FIG. 6C. Inaddition, the time zone of night indicated by the time parameter (thetime zone of 12 hours after the current time) matches the time zone ofnight indicated by the time information associated with the image shownin FIG. 6C. Therefore, the image data of the image shown in FIG. 6C isfound.

As described above, in the present embodiment, the position and thedirection in which the digital photo frame 1 is arranged, the distance(or depth) based on the digital photo frame 1, and the time are employedas parameters for searching for the image data. Then, the digital photoframe 1 searches for the image data based on the four parameters. As aresult, as compared with the conventional search method using a keyword,an image suitable for the actual environment where the digital photoframe 1 is located, i.e. the actual environment where the viewer ispresent, can be searched. This effect can also be exerted utilizing onlythe parameters of the position and direction in which the digital photoframe 1 is arranged. Moreover, this effect is made more remarkable byfurther utilizing the parameter of distance or depth based on thedigital photo frame 1 and the time parameter.

Moreover, the viewer can adjust the parameter of distance or depth andthe parameter of time just by performing an intuitive and simpleoperation using the distance direction knob 12 and the time knob 13. Asa result, for viewers, it becomes possible to realize a new way ofsearching for an image in combination with an idea of “what is there inthis direction away from here?” or “how does it change with time?”, andthus, a surprising image or an unpredictable image can be easilysearched. In other words, the viewer can easily perform operationsconsidering the actual environment, and as compared with theconventional act such as a slide show in which limited images arepassively viewed, a viewing act with active elements added can berealized. As a result, the viewer can easily view not only intendedimages, but also surprising images and unpredictable images.

The present invention is not limited to the present embodiment, andincludes variations and improvements thereto within a range that canachieve the object of the present invention.

For example, in the present embodiment, four types of parameters such asthe position and direction in which the digital photo frame 1 isarranged, the distance (or the depth) based on the digital photo frame1, and time are employed. However, it is only necessary for the positionand the direction to be employed as the types of the parameter. That is,only these two types of the parameters may be employed; however, byadding one type among parameters of the distance (or the depth) and thetime to these two types, three types of the parameters may also beemployed. Moreover, the other types of parameters such as parametersbased on an operation history or preference information of the viewermay be added.

For example, in the present embodiment, using the current time as areference value, as a method of calculating the time parameter, a methodof adding or subtracting the set value of the time knob 13 to or fromthe reference value is employed. However, the method of calculating thetime parameter is not particularly limited to the method of the presentembodiment. For example, it is not particularly necessary to use thecurrent time as the reference value, and an arbitrary time such as adefault fixed time may be used as the reference value to calculate thetime parameter.

In the present embodiment, the search destination of the image data isthe non-volatile database memory 15 or the network, for example.However, the search destination of the image data is not particularlylimited to the search destination of the present embodiment. Forexample, the removable media 29 in FIG. 3 or other devices (notillustrated) that are directly connected not via the network and thelike may be used as the search destination of the image data.

Incidentally, the series of processing according to the presentinvention can be executed by hardware and also can be executed bysoftware.

In a case in which the series of processing is to be executed bysoftware, the program configuring the software is installed from anetwork or a storage medium in a computer or the like. The computer maybe a computer incorporated in exclusive hardware. Alternatively, thecomputer may be a computer capable of executing various functions byinstalling various programs, i.e. a general-purpose personal computer,for example.

Although not illustrated, the storage medium containing the program canbe constituted not only by a removable media distributed separately fromthe device main body for supplying the program to a user, but also by astorage medium or the like supplied to the user in a state incorporatedin the device main body in advance. The removable media is composed of amagnetic disk (including a floppy disk), an optical disk, a magneticoptical disk, or the like, for example. The optical disk is composed ofa CD-ROM (Compact Disk-Read Only Memory), a DVD (Digital VersatileDisk), and the like. The magnetic optical disk is composed of an MD(Mini-Disk) or the like. The storage medium supplied to the user in thestate incorporated in the device main body in advance includes the ROMincluded in the memory 16 in FIG. 3 storing the program, thenon-volatile database memory 15 in FIG. 3, a hard disk, not illustrated,and the like, for example.

It should be noted that, in the present description, the step describingthe program stored in the storage medium includes not only theprocessing executed in a time series following this order, but also theprocessing executed in parallel or individually, which is notnecessarily executed in a time series.

What is claimed is:
 1. An image display device comprising: a front face;a back face which faces in a direction opposite to a direction in whichthe front face faces; a display portion configured to display an imageexpressed by image data wherein a display face of the display portion isprovided on the front face of the image display device, and faces in thesame direction as the front face of the image display device; a CPU; aposition sensor which is configured to function in cooperation with theCPU to be operable as a positional information acquiring unit whichacquires positional information indicating a current position where theimage display device is arranged; a direction sensor which is arrangedin the image display device and is configured to function in cooperationwith the CPU to be operable as a direction information acquiring unitwhich acquires a current direction in which the back face of the imagedisplay device is facing; an input device for inputting image data;wherein the CPU is configured to be operable as a search unit which isoperable to search for image data input via the input device which isassociated with positional information satisfying search conditions fromamong a plurality of pieces of image data, wherein the search unit uses,as a search condition, positional information of a location existing inthe current direction acquired by the direction information acquiringunit from the current position of the image display device indicated bythe positional information acquired by the positional informationacquiring unit; and wherein the CPU is configured to cause an imageexpressed by the image data found by the search unit to be displayed onthe display portion.
 2. An image display device as set forth in claim 1,further comprising a storage unit configured to store the plurality ofpieces image data input via the input device, wherein the search unitsearches for the image data from the storage unit.
 3. An image displaydevice as set forth in claim 1, wherein the input device comprises acommunication unit configured to communicate with an external device,wherein the search unit searches the external device with which thecommunication unit communicates for the image data.
 4. The image displaydevice according to claim 1, wherein the CPU is further configured to beoperable as a separated position setting unit that sets a position thatis separated from the current position where the image display device isarranged by a predetermined distance in the current direction acquiredby the direction information acquiring unit, wherein the search unituses positional information indicating the position set by the separatedposition setting unit as a search condition, and searches for image datainput via the input device which is associated with positionalinformation satisfying the search condition.
 5. The image display deviceaccording to claim 1, further comprising: a current time acquiring unitwhich acquires a current time; wherein the CPU is further configured tobe operable as a time setting unit which sets a time after apredetermined elapsed amount of time from the current time acquired bythe current time acquiring unit; wherein the search unit further usesthe time set by the time setting unit as a search condition, andsearches for image data associated with positional information and timeinformation satisfying the search conditions.
 6. An image display methodfor an image display device which includes (i) a front face, (ii) a backface which faces in a direction opposite to a direction in which thefront face faces, (iii) a display portion configured to display an imageexpressed by image data, wherein a display face of the display portionis provided on the front face of the image display device, and faces inthe same direction as the front face of the image display device, (iv) aCPU, (v) a position sensor which is configured to function incooperation with the CPU to be operable as a positional informationacquiring unit, (vi) a direction sensor which is arranged in the imagedisplay device and is configured to function in cooperation with the CPUto be operable as a direction information acquiring unit, and (vii) aninput device for inputting image data, the image display methodcomprising: acquiring, with the positional information acquiring unit,positional information indicating a current position where the imagedisplay device is arranged; acquiring, with the direction informationacquiring unit, a current direction in which the back face of the imagedisplay device is facing; searching, with the CPU, for image data inputvia the input device which is associated with positional informationsatisfying search conditions from among a plurality of pieces of imagedata, wherein, as a search condition, positional information of alocation existing in the acquired current direction from the currentposition of the image display device indicated by the acquiredpositional information is used; and causing, with the CPU, the displayportion to display an image expressed by the image data found by thesearching.
 7. A non-transitory computer-readable storage medium havingstored thereon a program that is executable by a computer forcontrolling an image display device which includes (i) a front face,(ii) a back face which faces in a direction opposite to a direction inwhich the front face faces, (iii) a display portion configured todisplay an image expressed by image data, wherein a display face of thedisplay portion is provided on the front face of the image displaydevice, and faces in the same direction as the front face of the imagedisplay device, (iv) a position sensor which is configured to functionin cooperation with the computer to be operable as a positionalinformation acquiring unit, (v) a direction sensor which is arranged inthe image display device and is configured to function in cooperationwith the computer to be operable as a direction information acquiringunit, and (vi) an input device for inputting image data, the programbeing executable by the computer to perform functions comprising:acquiring, with the positional information acquiring unit, positionalinformation indicating a current position where the image display deviceis arranged; acquiring, with the direction information acquiring unit, acurrent direction in which the back face of the image display device isfacing; searching for image data input via the input device which isassociated with positional information satisfying search conditions fromamong a plurality of pieces of image data, wherein, as a searchcondition, positional information of a location existing in the acquiredcurrent direction from the current position of the image display deviceindicated by the acquired positional information is used; and causingthe display portion to display an image expressed by the image datafound by the searching.